Shotgun shell tube or cartridge



y 1961 w. F. J. FIENUP ETAL 2,984,182

SHOTGUN SHELL TUBE 0R CARTRIDGE Filed Mar ch 5, 1958 FIG.3.

FIG.2.

WILLIAM F. J. FIENUP F JEROME J.GALBIERZ A ATTORNEY Patented May 16,196!

SHOTGUN SHELL TUBE R CARTRIDGE William F. J. Fienup, Berkeley, andJerome J. Galbierz,

Glendale, Mo., assignors to RC. Can Company, Overland, Mo., acorporation of Missouri Filed Mar. 3, 1958, Ser. No. 718,759

7 Claims. (Cl. 102-42) This invention relates generally to a cartridgefor a shotgun, and more specifically to a novel shell tube or casing fora cartridge, together with the method of manufacturing the same.

It is customary in the formation of shell tubes for shot shells to rollsheets of paper which have been covered with paste or other adhesiveupon a mandrel in such a manner that the wall of the tube is composed ofspiral convolutions of paper. In this process, a plurality of shelltubes are made simultaneously by selecting a sheet of paper of asuificient length. Subsequent to winding, the tube is severed at aplurality of spaced intervals of the correct length to form a shell tubefor a shot shell.

In order to waterproof the shell tube and to prevent internal charringof the paper upon firing of the cartridge, it is necessary to apply tothe sheet a coating material in precise zones. These coatings are wellknown in the art, and the use of wax, pitch, or asphalt for this purposeprovides the necessary characteristics to absorb the heat of the burningpowder so as to prevent charring and waterproof the shell tube againstmoisture. Any coating which is waterproof and will dissipate heatrapidly has been deemed suitable for the purpose.

1 This invention does not exclude the use of conventional coatingsheretofore used where these are desirable, but one object of theinvention is to construct a shot shell tube which has all of thedesirable characteristics of a metal tube and yet is cheaper tomanufacture than the conventional shotgun shell tube.

According to this invention, the inner surface of the shot shell tube isprovided with a liner of aluminum foil which is impervious to gases andmoisture, and resistant to charring in that the foil reflects anddissipates heat very rapidly. This is due to the inherentcharacteristics of the aluminum foil, which has a bright heat reflectingsurface and high heat conductivity. As a further insurance againstpenetration of moisture, the outer surface of the shell tube may also becovered with a wrapper of aluminum foil which may be attractivelycolored and decorated, if desired, by anodizing or printing.

While it might be possible to manufacture a shotgun shell casing with aninner metallic liner and an outer metallic wrapper by present processes,in which the shell tube is convolutely wound, it would require acomposite sheet of paper and foil with precise zones, of precise length,having strips of metallic foil of precise width. It is thereforeinescapable that the shell tubes would be more expensive to manufacturethan those presently on the market. Applicants have found, however, thatby departing from the conventional manufacturing processes, it ispossible not only to obtain the advantages inherent in such aconstruction, but also to lower the manufacturing costs to onecompetitive with conventional shot tubes. In this novel process formanufacture, paper tapes are helically wound on a mandrel in such amanner that the edges of a single tape form a tight butt joint, andthese joints are staggered throughout the length of the tube. This formsa continuous tube, which may then be severed at intervals to form shotshell tubes of the required length. The machine used in this process isthe same as that used in the manufacture of paper cans, and theresulting product is a shot shell tube with, what might be termed,spirally-wound layers of paper. This can better be defined ashelically-wound layers to differentiate from the spiral formed inconvolute winding. The inner and outer tapes are preferably compositesheets of paper coated with aluminum foil so as to form the inner linerand outer metallic wrapper. The other layers of paper need not be of thehighest quality in order to perform successfully. If desired, a finalwaterproofing step may be performed on the shot tubes by a simpledipping process.

Illustrated and described hereinafter is a single preferred form of theinvention, together with the preferred manner of manufacturing theinvention. Further objects and advantages will appear as thisdescription proceeds, when taken in conjunction with the accompanyingdrawings, in which: 1

Fig. 1 is a longitudinal sectional view of ashotgun shell.

Fig. 2 is a view illustrating the exterior of a shell tube such as usedin the shell shown in Fig. 1.

Fig. 3 is a fragmentary section on an enlarged scale illustrating theconstruction of the shell tube shown in Figs. 1 and 2; and I Fig. 4 is aschematic view illustrating the apparatus and manner of manufacture ofthe shell tubes shown in Figs. 2 and 3.

Since the invention here is concerned primarily with the shell tubeconstruction and its method of manufacture, a detailed description ofthe construction of .a shotgun shell does not appear necessary for acomplete understanding of the invention. However, in Fig. 1 theconstruction is shown generally.

The shot tube 1, later to be described in detail, has a metallic cap 2closing one end thereof, in which is located a primer 3. Surrounding theprimer 3 is a base 4.which supports the powder charge 5. Thischarge'm'ay be toafined by several wads such as 6, 7 and 8, the upperone of which is a short wad constructed to propel the shot pellets 9from the shot tube. These pellets are, in turn, confined within the tubeby a wad 10 held in place by the crimped edges 11 of the shot tube.

Fig. 2 illustrates a shot tube before being assembled and loaded. Aswill be seen, the shot tube 1 has an outer metallic wrapper 13, which isa continuous strip, helically wound, as at 14. The enlarged section inFig. 3 clearly illustrates the construction of the shot tube. The outerlayer is a composite sheet 15 formed of a metallic foil 13 and a similarpaper tape 16. Several intermediate layers of paper have been shown,such as 17, 18 and '19. These are added for strength purposes only, andto form a tube of suitable thickness to fit the firing chamber of thegun. The liner 20 is of metallic foil formed by helically winding acomposite sheet formed of a layer of paper 21 and a strip of metallicfoil 22.

Method of manufacture Fig. 4 illustrates a machine for winding the shotshell tubes in a continuous manner, and cutting them into proper length.This machine has a mandrel 25 for determining the internal size of theshot shell tube. In this particular case, the tube is formed of fivelayers, 15, 17, 18, 19 and 20. Consequently, there are five tapes, 15,17, 18, 19 and 20 fed into the machine from suitable rolls supported atan angle to the mandrel 25. The tapes 15, 17, 18, and 19 pass oversuitable adhesive-applying rollers, indicated as R, which coat the innerside of each of these tapes. The inner sides of both tapes 15 and 20 3carry the metallic foil strips 13 and 22 so as to provide the liner andthe wrapper of metallic foil.

Pulleys P, one of which is power driven, support the belt B, which iswrapped around the mandrel 25 and frictionally engages the outersurfaceof the tape 15 so as to simultaneously rotate the tube andcauseit to traverse the length of the mandrel 25 from left to right. Atraveling series of knife blades such as 30 and 35 are mountedon' ashaft 40 in such a manner as to engage the tube and'travel. with itduring engagement so as to sever it into the shot tubes 1, asillustrated.

It is contemplated that the tube maybe composed of difierent numbers oflayers and of difierent kinds of coated or uncoated tapes; likewise,that the apparatus upon which the tubes are made may take otherforms,all of which come within the scope ofthe appended claims.

We claim:

1. A shotgun shell of. the type having a tube and a base mountedthereon, said tube comprising separate layers of helically wound papertape with joints in successive layers in staggered relation and withsaid separate layers secured together to form an integral tube.

2. A shotgun shell of the type having a tube and a base thereon, saidtube comprising a plurality of separate, concentric, helically woundlayers of paper tape wound one upon the other with joints in successivelayers in staggered relation and with separate layers secured to form anintegral tube, said tube including an inner layer of paper tape with ametal coating.

3. A shotgun shell of the type having'a tube and a base thereon, saidtube comprising, a plurality of separate, concentric, helically woundlayers of paper tape wound one upon the other with joints in successivelayers in staggered relation and with separate layers secured togetherto form an integral tube, one of said layers of paper tape being, acomposite tape of a metal foil on a paper tape backing.

4. A shotgun shell of the type having a tube and a base thereon, saidtube comprising, a plurality of separate, concentric, helically woundlayers of paper tape wound one upon the other with joints in successivelayers in staggered relation and with separate layers secured togetherto form an integral tube, said tube including an inner layer and anouter layer of paper tape with each of said layers'having a metalcoating.

5. A shotgun shell of the type defined in claim 4 in which said innerlayer of paper tape and said outer layer of paper tape are formed ofpaper tapes with a metal foil on a paper tape backing to provide theinner and outer metal coating.

6. A shotgun shell of the type having a tube and a base thereon, saidtube comprising, a cylinder formed of a plurality of separate,concentric layers of paper tapes, each tape being helically wound toform a single layer, and said layers being helically wound in aconcentric manner one. upon the other with joints in successive layersin staggered relation and with separate layers secured to form anintegral tube, said tube including an inner layer and an outer layer ofpaper tape with each layer having a metal coating arranged to form ametal liner and wrapper for said tube.

7. A shotgun shell of the type having a tube and a base thereon, saidtube comprising a plurality of separate, concentric cylindrical layersof paper tape, each paper tape being helically wound one upon the otherto form said separate, concentric cylindrical layers of paper tape withjoints between tapes in successive layers in staggered relation, andsaid layers of paper tape being secured together to form an integralpaper tube.

References Cited in the file of this patent UNITED STATES PATENTS1,196,200 Batcher Aug. 29, 1916 1,567,631 Wheeler Dec. 29, 19251,944,970 Diefienbach Jan. 30, 1934 2,180,239 Holland et al Nov. 14,1939 2,192,923 Magill a Mar. 12, 1940 2,461,539 Fletcher Feb. 15, 19492,582,125 Holmes Jan. 8, 1952 2,623,445 Robinson Dec. 30, 1952 2,829,595Hitchens Apr. 8, 1958 FOREIGN PATENTS 755 Great Britain of 18681,129,156 France Jan. 1 6, 1957

